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UNIVERSITY  OF  ILLINOIS 

Agricultural  Experiment  Station 


BULLETIN  No.  188 


METHODS  OF  FERTILIZING 
SWEET  POTATOES 


BY  C.  E.  DURST 


URBANA,  ILLINOIS,  APRIL,  1916 


SUMMARY  OF  BULLETIN  No.  188 

1.  Fertilizer  experiments  were   conducted  with  sweet  potatoes  at  Anna,  in 
Union  county,  for  five  years.  Pago  269 

2.  Three  plats  were  fertilized  under  the  ridge  with  a  complete  home-mixed 
fertilizer,  steamed  bone,  and  manure,  respectively,  while  three  others  received  the 
same  fertilizers  broadcast.     Two  additional  plats  were  left  untreated  as  checks. 

Page  269 

3.  The   potatoes   were    graded    into    "table"    and    "seed"    potatoes,    and 
"strings,"  in  accordance  with  the  standards  used  in  that  section.  Page  270 

4.  As  the  price  of  sweet  potatoes  varies  somewhat,  according  to  the  time  of 
year  they  are  sold,  the  returns  were  estimated  on  the  basis  of  two  sets  of  prices. 

Page  271 

5.  Altho  all  the  fertilized  plats  produced  higher  average  yields  than  the  un- 
treated plats,  only  manure  or  steamed  bone  applied  under  the  ridge  gave  suf- 
ficiently increased  yields  to  return  any  material  profit  as  compared  with  the  check 
plats,  after  deducting  the  cost  of  the  fertilizer  and  neglecting  the  residues. 

Page  276 

6.  All  of  the  fertilizer  treatments  supplied  more  of  the  elements  for  which 
they  were  used  than  was  removed  by  the  sweet-potato  crops.  Page  277 

7.  Manure  under  the  ridge  gave  higher  net  returns  than  any  other  treatment, 
and  in  addition,  supplied  a  greater  excess  of  fertility  over  that  removed  in  the 
sweet  potatoes  than  any  treatment  except  manure  broadcast.     The  manure  also 
supplied  a  considerable  quantity  of  organic  matter.  Pages  276,  277 

8.  CONCLUSIONS.  Page  277 


METHODS  OF  FERTILIZING 
SWEET  POTATOES 

BY  C.  E.  DUEST,  ASSOCIATE  IN  OLERICULTURE 

The  method  of  application  of  fertilizers  has  an  important  influence 
on  the  yield  in  the  case  of  a  number  of  vegetable  crops.  In  order  to 
secure  data  on  certain  phases  of  this  question  in  relation  to  the  sweet 
potato,  tests  were  begun  by  the  Station  in  1910  and  were  continued  for 
five  years.  The  tests  were  conducted  at  Anna,  in  Union  county,  which 
is  in  the  leading  commercial  sweet-potato  section  of  Illinois. 

METHOD  OF  CONDUCTING  THE  TESTS 

The  land  used  in  this  experiment  was  of  the  unglaciated  yellow  silt 
loam  common  to  the  extreme  southern  part  of  Illinois.  The  tract  used 
had  a  slight  slope  to  the  north  and  was  perhaps  as  uniform  in  all 
respects  as  it  is  possible  to  obtain  in  that  section.  Eight  plats  were 
laid  out,  each  66  feet  by  20  feet.  Thus,  each  plat  consisted  of  exactly 
1/33  of  an  acre.  The  treatments  of  the  various  plats  each  year  were 
as  follows : 

Plat  1.  Check 

Plat  2.  Twenty  pounds  home-mixed  fertilizer  broadcast 

Plat  3.  640  pounds  manure  broadcast 

Plat  4.  Sixteen  pounds  steamed  bone  broadcast 

Plat  5.  Check 

Plat  6.  Twenty  pounds  home-mixed  fertilizer  under  ridge 

Plat  7.  640  pounds  manure  under  ridge 

Plat  8.  Sixteen  pounds  steamed  bone  under  ridge 

The  home-mixed  fertilizer  applied  to  Plats  2  and  6  consisted  of 
two  parts  steamed  bone,  two  parts  dried  blood,  and  one  part  potassium 
sulfate,  by  weight.  Since  each  plat  consisted  of  1/33  of  an  acre,  the 
rates  of  application  per  acre  were  660  pounds  home-mixed  fertilizer, 
10.56  tons  manure,  and  528  pounds  steamed  bone,  respectively. 

The  manure  applied  broadcast  to  Plat  3  was  applied  in  some  years 
before  plowing  and  in  other  years  after  plowing.  When  applied  after 
plowing,  it  was  thoroly  mixed  with  the  soil  by  disking  and  harrowing. 
The  home-mixed  fertilizer  and  the  steamed  bone  applied  broadcast 
were  in  all  cases  applied  after  plowing  and  disking,  and  were  mixed 
with  the  soil  by  harrowing  before  the  ridges  for  planting  the  sweet 
potatoes  were  made.  For  applying  the  fertilizers  and  manure  under 
the  ridges  in  Plats  6,  7,  and  8,  the  land  was  plowed,  disked,  and  har- 
rowed the  same  as  for  the  other  plats.  Then  a  furrow  was  made  where 
each  row  of  sweet  potatoes  was  to  be  planted.  The  fertilizer  or  manure 
was  scattered  in  the  furrow,  after  which  a  ridge  was  made  directly 
over  it,  with  the  tools  usually  employed  in  preparing  ridges  for  the 

760 


270  BULLETIN  No.  188  [April, 

planting  of  sweet  potatoes.  Six  ridges,  for  planting  as  many  rows, 
were  made  lengthwise  of  each  plat.  Thus  the  rows  were  31/^  feet 
apart. 

The  sweet-potato  plants,  which  had  been  grown  in  hotbeds,  were 
planted  by  means  of  a  spade,  as  is  customary  in  the  locality  in  which 
these  experiments  were  conducted.  The  plants  were  placed  approxi- 
mately sixteen  inches  apart  in  the  row.  They  were  cared  for  in  the 
usual  manner,  all  plats  being  treated  alike  as  to  tillage  and  incidental 
care.  Each  year  the  crop  was  allowed  to  grow  as  late  in  the  season 
as  seemed  reasonably  safe,  the  harvesting  dates  varying  from  October 
11  to  21. 

METHOD  OF  GRADING  THE  CROP 

As  soon  as  dug,  the  sweet  potatoes  were  separated  into  three 
grades,  according  to  the  method  used  by  commercial  growers  in  the 
locality.  All  potatoes  having  a  diameter  of  iy2  inches  or  more, 
unless  badly  distorted,  were  classified  as  "table"  potatoes.  In  the 
next  grade,  designated  as  "seed"  potatoes,  shape  as  well  as  size  was 
considered.  All  comparatively  short,  smooth  potatoes  of  fairly  good 
size  (i.e.,  from  about  1  to  iy2  inches  in  diameter)  were  included 
in  this  grade.  Any  specimens  showing  a  tendency  toward  lengthi- 
ness  were  discarded.  All  potatoes  too  deficient  in  size  or  shape 
to  be  included  in  either  of  the  above  grades  were  designated  as 
"strings."  On  account  of  the  rigid  selection,  on  the  basis  of  shape, 
for  the  seed  grade,  some  potatoes  of  fairly  good  size  Avere  included  in 
the  "strings." 

RESULTS  OF  THE  TESTS 

The  yields  of  sweet  potatoes  from  the  various  plats  each  year, 
graded  into  table  potatoes,  seed  potatoes,  and  "strings,"  are  given  in 
Table  1.  The  figures  used  in  this  table  indicate  pounds  per  plat,  the 
weights  being  taken  in  the  field  at  digging  time.  For  fertilizer  treat- 
ment of  the  different  plats,  see  page  269. 

The  percentages  of  the  crop  graded  as  table  potatoes  and  as 
' '  strings ' '  from  each  plat  each  year  are  given  in  Table  2.  The  figures 
for  1913  are  omitted  in  this  and  following  tables  because  of  unac- 
countable discrepancies  in  the  checks.  The  averages  for  the  four  years 
from  each  plat  are  also  given.  These  averages  have  been  calculated 
from  the  total  product  from  a  given  plat  for  the  four  years,  rather 
than  from  the  percentages  for  each  year. 

The  yields  of  table  and  seed  potatoes  from  the  various  plats,  cal- 
culated to  terms  of  bushels  per  acre,  are  given  in  Table  3.  In  making 
these  calculations,  it  has  been  assumed  that  55  pounds  of  sweet  pota- 
toes are  equivalent  to  one  bushel. 

Obviously  the  value  of  a  fertilizer  treatment  is  determined  largely 
by  the  prices  received  for  the  products.  As  the  price  of  sweet  potatoes 
varies  from  season  to  season  and  according  to  the  time  of  year  they 


1916]  METHODS  OF  FERTILIZING  SWEET  POTATOES  271 

are  marketed,  the  figures  in  Tables  4  and  5  have  been  calculated  on  the 
basis  of  two  sets  of  prices.  A  common  price  in  southern  Illinois  at  dig- 
ging time  in  October  is  50  cents  per  bushel  for  the  table  grade  and  25 
cents  per  bushel  for  the  seed  grade.  The  values  in  Table  4  were 
calculated  on  the  basis  of  these  prices. 

If  the  crop  is  stored  for  a  time,  better  prices  may  usually  be  se- 
cured, tho  they  are  quite  variable  from  season  to  season.  Between 
Thanksgiving  and  February  1,  when  the  bulk  of  the  stored  table  pota- 
toes is  usually  sold,  the  prices  range  between  50  cents  and  $1  per 
bushel,  as  a  rule ;  occasionally,  a  higher  point  than  the  latter  figure  is 
reached.  The  seed  grade  is  ordinarily  sold  in.  April,  when  the  price 
is  about  $1  per  bushel.  The  demand  for  this  grade  is  not  great,  how- 
ever, owing  to  the  fact  that  many  growers  save  their  own  seed.  Consid- 
ering all  the  circumstances,  it  is  believed  that  75  cents  per  bushel  for 
both  grades  represents  a  fair  price  for  stored  potatoes.  Table  5  pre- 
sents the  values  calculated  on  this  basis. 

The  ' '  strings ' '  were  not  considered  in  Tables  4  and  5  in  determin- 
ing the  value  of  the  crop,  since  this  grade  usually  is  not  sold  but  is 
left  on  the  ground  or  fed  to  stock. 

In  both  Tables  4  and  5,  the  value  per  acre  of  the  crop  from  each 
plat  is  given  in  the  column  headed  ' '  Gross, ' '  under  each  year.  In  the 
column  headed  ' '  Net, ' '  under  each  year,  is  given  the  value  of  the  crop 
from  each  plat,  minus  the  cost  of  the  fertilizer  applied  to  the  given 
plat.  The  cost  of  the  fertilizers  is  based  upon  the  following  prices  per 
ton  for  the  various  materials :  steamed  bone,  $25 ;  dried  blood,  $45 ; 
potassium  sulfate,  $50 ;  manure,  $1.50.  These  prices  prevailed  during 
the  time  the  experiments  were  conducted.  This  would  make  the  cost 
per  acre  for  the  different  treatments  as  follows :  Plats  2  and  6,  $12.54 ; 
Plats  3  and  7,  $15.84 ;  Plats  4  and  8,  $6.60. 

In  Table  6  is  given  the  total  number  of  bushels  of  sweet  potatoes 
produced  per  acre  under  each  treatment  for  the  four  years  combined ; 
the  amounts  of  fertilizing  elements  furnished  during  that  time  by  the 
various  treatments ;  the  quantities  of  each  element  removed  from  the 
soil  by  the  potatoes;  and  the  excess  supplied  by  the  fertilizers  over 
the  amounts  contained  in  the  crops.  The  fertility  content  of  the  sweet 
potatoes  is  based  upon  the  figures  presented  in  Circular  182  (page  5) 
of  this  Station.  The  amounts  of  the  fertilizing  elements  supplied  by 
the  treatments  are  based  upon  the  following  figures : 

Dried  blood,  14  percent  nitrogen 

Steamed  bone,  12%  percent  phosphorus 

Sulfate  of  potash,  421/->  percent  potash 

Manure,  10  pounds  nitrogen,  3  pounds  phosphorus, 
and  8  pounds  potash  per  ton1 

No  allowance  has  been  made  for  the  small  amount  of  nitrogen  con- 
tained in  steamed  bone.  The  "strings"  were  not  considered,  since 
they  were  left  on  the  ground  and  their  fertility  content  was  thus  re- 
turned to  the  soil. 

'Horse  manure,  shipped  from  St.  Louis,  Missouri,  was  used  in  these  experi- 
ments. 


272 


BULLETIN  No.  188 


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METHODS  OF  FERTILIZING  SWEET  POTATOES 


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rHCM          CO^mtO          t»OO 

1916]  METHODS  OF  FERTILIZING  SWEET  POTATOES  275 

DISCUSSION  OF  THE  RESULTS 

An  examination  of  the  figures  in  Table  2  shows  that  in  two  years  of 
the  four  (1910  and  1914)  both  check  plats  gave  lower  percentages  of 
table  potatoes  than  any  of  the  fertilized  plats.  In  1911,  only  Plat  4, 
receiving  steamed  bone  broadcast,  yielded  a  lower  percentage  than 
either  check  plat.  In  1912,  Plats  4  and  8,  receiving  steamed  bone 
broadcast  and  under  the  ridge,  respectively,  gave  slightly  lower  per- 
centages than  Plat  5,  but  higher  than  Plat  1,  the  other  check.  The 
four-year  averages  show  that  the  percentage  of  table  potatoes  was 
higher  for  each  of  the  fertilized  plats  than  for  either  check  plat. 

Table  2  shows  further  that  in  two  years  of  the  four,  Plat  6,  receiv- 
ing home-mixed  fertilizer  under  the  ridge,  gave  a  higher  percentage 
of  table  potatoes  than  the  corresponding  plat  fertilized  broadcast  (Plat 
2) ,  and  that  the  reverse  was  true  the  other  two  years.  Plat  7,  receiving 
manure  under  the  ridge,  yielded  a  higher  percentage  of  table  potatoes 
every  year  of  the  four  than  Plat  3,  which  received  manure  broadcast. 
In  two  years  of  the  four,  Plat  8,  receiving  steamed  bone  under  the 
ridge,  gave  a  higher  percentage  of  table  potatoes  than  Plat  4,  fertilized 
with  steamed  bone  broadcast;  in  a  third  year,  the  percentages  were 
practically  equal.  The  four-year  averages  favor  the  application  of 
fertilizer  under  the  ridge  except  in  the  case  of  the  home-mixed  fer- 
tilizer. The  highest  percentage  of  table  potatoes  and  the  lowest  per- 
centage of  ' '  strings ' '  for  the  four  years  as  a  whole  were  secured  from 
Plat  7,  fertilized  with  manure  under  the  ridge. 

The  figures  in  Table  3  show  that  all  the  fertilized  plants  gave  mark- 
edly better  average  yields  of  table  potatoes  than  either  of  the  check 
plats.  In  1910  and  1914,  both  check  plats  yielded  fewer  bushels  of 
table  potatoes  than  any  of  the  fertilized  plats;  in  1911  there  was  only 
one  exception  (Plat  4)  ;  and  in  1912  there  were  two  (Plats  4  and  8). 
The  highest  yield  of  table  potatoes  was  secured  every  one  of  the  four 
years  from  Plat  7,  fertilized  with  manure  under  the  ridge,  and  this 
plat  was  distinctly  superior  to  all  others  in  average  yield  of  table 
potatoes  for  the  four  years.  The  second  highest  average  yield  was 
from  Plat  3,  which  was  manured  broadcast. 

In  comparing  the  results  from  fertilizing  under  the  ridge  with  those 
from  fertilizing  broadcast  (Table  3),  it  is  seen  that  in  every  year  of 
the  four,  the  home-mixed  fertilizer  produced  a  larger  yield  of  table 
potatoes  when  applied  under  the  ridge  than  when  applied  broadcast : 
in  every  year  of  the  four,  the  manure  under  the  ridge  produced  a 
larger  yield  than  the  manure  broadcast ;  and  the  steamed  bone  gave 
better  results  under  the  ridge  three  years  of  the  four.  The  four-year 
average*  was,  in  the  case  of  each  fertilizer,  distinctly  in  favor  of  the 
plat  in  Avhich  the  material  was  applied  under  the  ridge. 

While  favorable  results  followed  the  use  of  the  fertilizers  in  nearly 
all  cases,  the  figures  in  Tables  4  and  5  show  that  one  must  take  into 


276  BULLETIN  No.  188  [April, 

account  the  prices  likely  to  be  received  for  the  potatoes  when  consid- 
ering the  advisability  of  using  any  of  these  treatments. 

At  50  cents  per  bushel  for  the  table  potatoes  and  25  cents  for  the 
seed  grade  (Table  4),  there  was  a  general  increase  in  the  net  value  of 
the  crop  in  only  two  years  of  the  four.  In  three  years  of  the  four, 
home-mixed  fertilizer  broadcast  gave  lower  net  returns  than  the  aver- 
age of  the  check  plats.  The  same  fertilizer  applied  under  the  ridge 
gave  better  net  returns  than  the  average  of  the  check  plats  in  only  two 
years  of  the  four,  the  four-year  averages  being  about  equal.  Manure 
broadcast  gave  practically  the  same  net  returns  as  the  average  of  the 
checks  two  years  of  the  four ;  in  one  it  gave  a  net  return  of  about  $6 
higher;  and  in  the  fourth  it  gave  about  $14  lower.  The  four-year 
averages  show  a  lower  net  return  from  manure  broadcast  than  from 
either  of  the  check  plats.  Manure  under  the  ridge  gave  higher  net  re- 
turns than  the  check  average  two  years  of  the  four;  in  another  the 
results  were  practically  the  same ;  and  in  the  fourth  manure  under  the 
ridge  gave  a  net  return  of  about  $7  lower  than  the  check  average. 
Steamed  bone  under  the  ridge  gave  better  net  returns  than  the  check 
average  two  years  of  the  four ;  in  another  the  returns  were  practically 
equal;  and  in  the  fourth  there  was  a  deficiency  of  about  $10  for 
steamed  bone  under  the  ridge.  The  four-year  net  return  from  steamed 
bone  under  the  ridge  was  about  $5  higher  than  the  check  average.  The 
four-year  averages,  as  a  whole,  show  that  only  in  Plats  7  and  8,  fer- 
tilized under  the  ridge  with  manure  and  steamed  bone,  respectively, 
were  the  increases  in  yield  sufficient  to  give  any  material  profit  as 
compared  with  the  check  plats,  after  deducting  the  cost  of  the  fer- 
tilizers. 

At  75  cents  per  bushel  for  both  table  and  seed  potatoes  (Table  5), 
the  results  were  somewhat  more  favorable  as  a  whole  toward  the  fer- 
tilizer treatments.  Home-mixed  fertilizer  broadcast  gave  better  net 
returns  than  either  of  the  check  plats  in  only  two  years  of  the  four, 
the  four-year  averages  being  about  equal.  The  same  fertilizer  applied 
under  the  ridge  gave  higher  net  returns  than  the  check  average  two 
years  of  the  four,  and  in  one  other  they  were  practically  equal.  The 
four-year  net-return  averages  favor  the  home-mixed  fertilizer  under 
the  ridge  over  no  treatment  by  only  about  $3  per  acre.  Manure 
broadcast  exceeded  the  check  average  in  net  returns  three  years  of  the 
four,  the  four-year  net  returns  being  exactly  $6  in  favor  of  the  manure. 
Manure  under  the  ridge  gave  higher  net  returns  than  the  check  aver- 
age three  years  of  the  four,  and  in  the  fourth  the  decrease  amounted 
to  only  about  $5  per  acre.  The  four-year  net  returns  favor  manure 
under  the  ridge  over  no  treatment  by  about  $20  per  acre.  Steamed 
bone  broadcast  gave  higher  net  returns  than  the  check  average  in 
only  two  of  the  four  years,  and  lower  returns  in  the  other  two,  tho 
the  superiority  in  the  first  case  exceeded  the  inferiority  in  the  sec- 
ond. The  four-year  averages  favor  steamed  bone  under  the  ridge 
over  no  treatment  by  about  $11  per  acre.  As  with  the  prices  used  in 


1916]  METHODS  OF  FERTILIZING  SWEET  POTATOES  277 

calculating  Table  4,  only  manure  and  steamed  bone  applied  under 
the  ridge  gave  sufficiently  increased  yields  to  cause  any  material 
profit  as  compared  with  the  check  plats,  after  deducting  the  cost  of 
the  fertilizers. 

In  considering  the  advisability  of  using  any  of  the  above  treat- 
ments one  should  bear  in  mind  two  additional  factors.  No  allowance 
has  been  made  for  the  labor  of  applying  the  fertilizers,  which  would 
be  an  important  -item  in  the  case  of  application  under  the  ridges. 
On  the  other  hand,  the  fertility  supplied  by  the  fertilizer  treatments 
during  the  four  years  was  not  all  consumed  by  the  sweet-potato  crops. 
Table  6  shows  that  all  of  the  treatments  furnished  more  of  the  elements 
for  which  the  fertilizers  were  used  than  was  removed  by  the  crops. 
Manure  under  the  ridge  (Plat  7)  not  only  produced  larger  yields  and 
greater  net  returns  (Tables  4  and  5)  than  any  of  the  other  treatments, 
but  left  more  fertility  in  the  soil,  as  a  whole,  than  any  treatment,  ex- 
cept that  given  Plat  3,  which  ranked  only  slightly  higher.  The  ma- 
nure applied  to  Plats  3  and  7  furnished  a  considerable  amount  of  or- 
ganic matter  in  addition  to  the  fertilizing  elements,  something  which 
cannot  be  said  of  any  of  the  other  treatments.  The  manure  treat- 
ments (Plats  3  and  7)  each  left  about  265  pounds  more  of  the  element 
nitrogen  in  the  soil  per  acre  during  the  four  years  than  the  home- 
mixed  fertilizer  treatments  (Plats  2  and  6),  slightly  more  phosphorus, 
and  about  100  pounds  more  potash.  The  steamed  bone  (Plats  4  and 
8)  left  about  130  pounds  more  of  phosphorus  in  the  soil  than  the 
manure.  It  should  be  borne  in  mind  that  the  nitrogen  is  subject  to  loss 
by  drainage  and  oxidation  and  that  only  part  of  the  excess  of  this  ele- 
ment, therefore,  would  be  available  for  future  crops.  Phosphorus  and 
potash  are  not  lost  from  the  soil  to  any  appreciable  extent  thru  these 
causes,  hence  practically  all  of  the  excess  of  these  elements  supplied 
could  be  used  by  succeeding  crops. 

CONCLUSIONS 

1.  Under  the  conditions  of  these  experiments,  each  of  the  fer- 
tilizer treatments  described  is  capable  of  increasing  the  percentage 
of  table  potatoes  produced.    With  the  possible  exception  of  the  home- 
mixed  fertilizer,  higher  percentages  of  table  potatoes  are  produced 
when  the  fertilizer  is  applied  under  the  ridge  than  when  broadcasted. 

2.  Each  of  the  fertilizer  treatments  increases  the  yields  as  well 
as  the  percentages  of  table  potatoes.    Higher  yields  are  secured  when 
the  fertilizer  is  applied  under  the  ridge  than  when  applied  broadcast. 

3.  The  prices  likely  to  be  received  for  the  crop  should  be  taken 
into  account  when  considering  the  advisability  of  employing  any  of 
these  treatments. 

4.  Only  manure  or  steamed  bone  applied  under  the  ridge  is  likely 
to  give  a  material  increase  in  the  net  value  of  the  crop,  after  deduct- 
ing the  cost  of  th^  fertilizer. 


278 


BULLETIN  No.  188 


[April, 


5.  As  is  generally  the  case,  the  results  are  somewhat  more  favor- 
able toward  the  use  of  the  fertilizers  when  the  prices  received  for  the 
potatoes  are  high  than  when  they  are  low. 

6.  It  is  a  significant  fact  that  a  relatively  small  proportion  of 
the  elements  supplied  by  the.  fertilizers  is  removed  by  the  sweet  pota- 
toes, and  that  a  large  part  of  the  fertility  remains,  therefore,  for 
subsequent  crops. 

7.  Manure  applied  under  the  ridge  not  only  results  in  the  highest 
net  returns,  but  leaves  more  fertilizer  value  in  the  soil  than  any  other 
treatment  except  manure  broadcast.     This  exception  is  explained  by 
the  fact  that  manure  broadcast,  while  it  supplies  the  same  amount  of 
fertility  as  manure  under  the  ridge,  gives  a  lower  yield  of  potatoes. 
The  manure  also  adds  considerable  organic  matter  to  the  soil,  which 
cannot  be  said  of  any  other  treatment. 


SECTIONAL  VIEW  OF  EXPERIMENTAL  PLATS  AT  ANNA,  1911 


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UNIVERSITY  OF  ILLINOIS-URBANA 


